Arfa Daily wrote in message
...


"N_Cook" wrote in message
...
Serious amount of damage on one ch from someone using handfulls of
white
goo under the TO3 ," insulating" the pins as they were inserted through
it
into the TO3 sockets, causing sparking and destruction of that socket
and
a
load of colateral.

Plenty of info out there

http://stomach.v2.nl/docs/Hardware/S...1.5a-PM1200%20
Service%20Schematics-1.pdf
eservice etc

But nowhere can I find the ,no load, quiescent draw from the mains. I
have
bypassed / isolated the mains triac board and powering via metered
variac
to
the transformer direct at these preliminary stages of powerup. Running
at
50
percent mains about 0.1 amp current draw and all monitored DC levels
match
between channels and clean signal on output and ps rails half expected
values. Increase to 60 percent and draw climbs abruptly to 0.5 amp . So
far
quickly returned to 50 percent and nothing obviously overheating. Anyone
happen to know the expected draw?



May not be a genuine problem that you're seeing. Like you, I always bring
suspect amps up with a variac, but on more than a few occasions, I've seen
amps that just do not like reduced supply input levels, and behave exactly
as you describe, but with no obvious signs of distress from the output
stages. If you (dare to) keep going up, suddenly, everything evens out,
and
the input current returns to a more 'normal' level.

Arfa



I had to check whether I'd connected mains to one 120V primary by mistake as
it was that sort of effect but without saturation noise from the
transformer. Will return to it later today and also try engaging the triac
section as I've not got my head around the on demand draw triac instead of
good load/bad load or brownout triac